Archives par mot-clé : Amazon

La forêt amazonienne n’est pas le poumon de la planète

by SCE-INFO, 30 août 2019 in ScienceClimatEnergie


La forêt amazonienne fait beaucoup parler d’elle en ce moment. Selon le journal Le Monde mais également selon de nombreux autres médias, la forêt amazonienne est ravagée par des incendies d’une ampleur inédite, et ce depuis plusieurs semaines. Sans nier les feux ni l’importance de cette forêt au niveau de sa biodiversité, nous tenons à dénoncer quelques contre-vérités qui ont circulé.

1/ La forêt amazonienne n’est pas le poumon de la planète

Scientifiquement, l’expression “poumon de la planète” pour désigner l’Amazonie est fausse et prétendre que l’Amazonie produit 20% de notre oxygène — une assertion du Président français Macron lors du récent sommet du G7 — est fausse. Tout d’abord un poumon ne produit pas d’oxygène mais en consomme… Mais passons ce détail. Ce qu’il faut retenir est ceci : le bilan entre photosynthèse et respiration pour cet écosystème est nul du point de vue de l’oxygène [1] . La forêt amazonienne ne produit donc quasi pas d’oxygène, tout comme les océans, lorsque l’on considère le bilan net (photosynthèse + respiration). Tout ceci est même rappelé sur page Wikipedia consacrée à la forêt amazonienne, ou encore sur le site web du National Geographic.

Pour ceux qui ont du mal à lire en anglais, vous pouvez également lire le site français du Huffington Post, cette page de Planet Terre écrite en juin 2000, ou cet article écrit dans Le Parisien.

Pour ceux qui se posent la question de l’origine de l’oxygène que nous respirons (21% dans l’atmosphère actuelle), voici la réponse : nous respirons essentiellement un O2 libéré par des végétaux anciens (par exemple datant du Carbonifère) devenus matière organique fossile (ce carbone n’est pas dégradé par les bactéries des sols et sédiments et donc ne consomme pas d’oxygène atmosphérique). La page de Planet Terre citée précédemment explique parfaitement ce phénomène.

Figure 1. Nombre de feux de forêt au Brésil entre 2004 et 2019.
Source : Libération.

Amazon Wildfires Are Horrifying, But They’re Not Destroying Earth’s Oxygen Supply

by Scott Denning, August 22, 2019 in LiveSci=nce


Fires in the Amazon rainforest have captured attention worldwide in recent days. Brazilian President Jair Bolsonaro, who took office in 2019, pledged in his campaign to reduce environmental protection and increase agricultural development in the Amazon, and he appears to have followed through on that promise.

The resurgence of forest clearing in the Amazon, which had decreased more than 80% following a peak in 2004, is alarming for many reasons. Tropical forests harbor many species of plants and animals found nowhere else. They are important refuges for indigenous people, and contain enormous stores of carbon as wood and other organic matter that would otherwise contribute to the climate crisis.

Some media accounts have suggested that fires in the Amazon also threaten the atmospheric oxygen that we breathe. French President Emmanuel Macron tweeted on Aug. 22 that “the Amazon rain forest — the lungs which produces 20% of our planet’s oxygen — is on fire.”

Don’t hold your breath

Even though plant photosynthesis is ultimately responsible for breathable oxygen, only a vanishingly tiny fraction of that plant growth actually adds to the store of oxygen in the air. Even if all organic matter on Earth were burned at once, less than 1% of the world’s oxygen would be consumed.

In sum, Brazil’s reversal on protecting the Amazon does not meaningfully threaten atmospheric oxygen. Even a huge increase in forest fires would produce changes in oxygen that are difficult to measure. There’s enough oxygen in the air to last for millions of years, and the amount is set by geology rather than land use. The fact that this upsurge in deforestation threatens some of the most biodiverse and carbon-rich landscapes on Earth is reason enough to oppose it.

Fake News and Fires in the Amazon

by Donna Laframboise, August 23, 2019 in BigPicturesNews


Politicians and government officials like to talk as though it’s possible to stamp out fake news. It isn’t.

Fake news is as old as humanity. After Aristotle incorrectly claimed women had fewer teeth than men, generations of highly educated people believed it.

Rajendra Pachauri was called “the UN’s top climate scientist” by the BBC – and a “Nobel laureate” by the New York Academy of Sciencesmagazine. Neither statement was true.

Pachauri’s doctorate wasn’t in climatology, but in industrial engineering and economics. And the fact that he accepted the 2007 Nobel Peace Prize on behalf of the UN organization he chaired doesn’t make him or any other person affiliated with that organization a Nobel laureate.

Published in 2008 and 2009, these inaccurate statements have never been corrected. In other words, we’re surrounded by fake news. And always will be. Humans are frequently mistaken. Organizations, as well as individuals, post things on the Internet before double-checking.

While media outlets are supposed to be more reliable than your brother-in-law, that seems less true every day. Over the past week, people have shared a CNN headline on Facebook that declares: “The Amazon rainforest is burning at a record rate” (see the screengrab from my own Facebook feed, at the top of this post).

If you click through to the CNN website, you’ll find a few extra words: “…research center says.” But the primary statement is misleading. Which means that millions have been alarmed unnecessarily – including a lovely, smart, young mother of my acquaintance.

Over at the website of National Geographic, a headline falsely declares: Brazil’s Amazon is burning at record rates – and deforestation is to blame. The second half of that assertion is vigorously disputed here.

Why Everything They Say About The Amazon, Including That It’s The ‘Lungs Of The World,’ Is Wrong

Amazon fires: how celebrities are spreading disinformation

The Amazon Is Not Earth’s Lungs: Humans could burn every living thing on the planet and still not dent its oxygen supply

Is Amazon Rainforest Burning At Record Rates? What Is The Way Forward?

Lies, Damn Lies, And Rainforest Fear-Mongering

Annual Amazon farmland burn sets records for international outrage

Amazon fires: What about Bolivia?

Stop Sharing Those Viral Photos of the Amazon Burning

The Three Most Viral Photos of the Amazon Fire Are Fake. Here Are Some Real Ones to Share.

What Satellite Imagery Tells Us About the Amazon Rain Forest Fires

The myth of ecocide: So many lies are being told about the Amazon fires

Why shouldn’t Brazilians burn down trees?

Sugar cane, Palm oil, and Biofuels in the Amazon

Amazonie : fake news, désinformation, manipulation !

by Jo Moreau, 26 août 2019 in Contrepoints


L’ avalanche d’articles, de photos et d’avis de personnalités de tous horizons sur les incendies qui ravagent l’Amazonie constitue une illustration parfaite du sale boulot de manipulation de l’opinion publique exercée par les médias, et porteur de l’amalgame trompeur diffusé jour après jour entre protection de l’environnement et réchauffement climatique.

La première chose qui a attiré mon attention est le rapport fait entre le nombre d’incendies constatés en 2019, avec la situation en… 2018. Il est à peine croyable qu’une comparaison aussi peu significative sur le plan statistique et trompeuse sur le plan historique ait été diffusée sans aucune réserve par tous les médias mondiaux, mais serve de surcroît les intérêts d’hommes et de femmes politiques, à commencer par le leader auto-proclamé de l’Union Européenne et porte-drapeau mondial de l’écologisme, j’ai nommé le président Macron.

Illustré par une photo « détournée », son récent tweet sur le sujet résume parfaitement l’amalgame entretenu par les sauveurs de la planète sur base de fake news :

« Notre maison brûle. Littéralement. L’Amazonie, le poumon de notre planète qui produit 20 % de notre oxygène, est en feu. C’est une crise internationale. Membres du G7, rendez-vous dans deux jours pour parler de cette urgence. »

Alors, soit le président Macron est mal informé, soit il suit aveuglément les avis très orientés d’ONG n’ayant aucune légitimité scientifique ou démocratique. Le problème est que la majorité de ceux qui nous gouvernent a une démarche identique.

Mais reprenons les choses dans l’ordre.

FAKE NEWS

Je place sous ce titre l’emploi par les médias ou sur les réseaux sociaux de photos parfois anciennes, non pas « fausses », mais tout à fait étrangères avec la situation actuelle en Amazonie.

Il s’agit d’une tactique souvent employée, destinée à émouvoir le public et l’orienter dans le sens voulu. Le choix des photos qui illustrent un article a une grande importance. Ainsi, les photos de dirigeants politiquement incorrects montrent souvent des visages grimaçants ou dans des poses peu avantageuses, tandis que les dirigeants idéologiquement corrects (aux yeux des médias) nous sont montrés souriants et sympathiques.

Mais l’emploi massif de ces photos « détournées » était tellement flagrant qu’après les avoir abondamment publiées, l’ensemble de la presse émit dans un deuxième temps des réserves prudentes quant à leur origine, ce qui lui permit accessoirement de se draper dans une démonstration émouvante d’objectivité.

DÉSINFORMATION

Voir aussi ici
(Une Amazonie bien commode pour la politique idiote de Macron)

Amazon Rain Forest Fires: Here’s What’s Really Happening

by Alexandria Symonds, August 23, 2019 in TheNewYorkTimes


 

These fires were not caused by climate change. They were, by and large, set by humans. However, climate change can make fires worse. Fires can burn hotter and spread more quickly under warmer and drier conditions.

When it comes to the future of climate change, widespread fires contribute a dual negative effect. Trees are valuable because they can store carbon dioxide, and that storage capacity is lost when trees burn. Burning trees also pumps more carbon into the atmosphere.

Is Amazon Rainforest Burning At Record Rates? What Is The Way Forward?

by R. Walker, August 21, 2019 in Science20


Short summary: we have had wild fires for many years now in the Amazon, even in the tropical rainforest – mainly started by humans for forest clearing and ranching. It is not enough to impact significantly on the Paris agreement pledges yet, though it is important in the long term if this continues for decades. It does of course have major and immediate impacts on forest residents, nature services and the biodiversity in Brazil.

This image is being shared widely, for instance in National Geographic’s “The Amazon is burning at record rates – and deforestation is to blame”. Similarly, the BBC is reporting it as ‘Record number of fires’ in Brazilian rainforest.

Yet, NASA’s own description for this photo says that it is burning at close to the average for the last 15 years. So, what is going on here?

APOLOGIES – UPDATE FROM NASA FROM 19TH AUGUST – THEY NOW CONFIRM INPE INSTEAD OF SAYING IT IS BELOW AVERAGE

Previous version of this article was mistaken. I have made a copy on my website here (the comments on this article are based on that earlier version):

NASA Say Amazon Rainforest Burning At Close To Average Rates – Yet Many News Stories Say Record Rates – Which Is It?

It accurately summarized the article it linked to from NASA (Fires in Brazil) and that page showed as updated on 22nd August which lead me to believe it was up to date. But apparently it isn’t, that’s just the date for a minor update of the page.

Amazon Fire History Since 2003

by Les Johnson, August 23, 2019 in WUWT


We are told that Amazon fires are at record levels right now. This is a blatant lie. The only “record” is that Amazonian fires have DECREASED over the “record”.

This (is) what the data actually looks like, to August 22. Yes, its updated daily.

This comes from a wonderful site, https://www.globalfiredata.org/forecast.html#elbeni

It uses NASA MODIS data, from the Terra and Aqua satellites, and is updated daily. By going to the website, you can look at individual regions in the Amazon, or as I have done, look at the totals for the Amazon. This site also has global data, but I am only looking at the Amazon region here.

The Interactive Graphs are very informative. Hovering the cursor over the graph will show the data at that point.

You can highlight individual years, by clicking on a year in the legend at the bottom of the graph. That year remains bright, while the rest are dimmed. Using Eyeball Mark 1 Trend Indicator (EBM1TI), 2019 is slightly high, but not at record levels. Not even close.

One thing I saw by looking at each year, was a rough pattern – one or two bad years, one or two years at much lower levels, then a bad year. This pattern is there until 2010. 2010 was the last “bad year”. Levels since 2010 have been 1/2 or less of the “bad years”. The old pattern has been broken.

 

 

See also here